1. Field of the Invention
The present invention relates to aircraft, and more particularly to a system for enabling an aircraft to accomplish extremely short takeoffs and landings.
2. Description of the Related Art
Navy and Marine aircraft design for carrier operations have significant structural weight and cost penalties to withstand the loads associated with catapult launch and arrested landings. The speeds at which carrier aircraft land lead to high pilot workload and safety problems. Current vertical/short takeoff and landing (V/STOL) aircraft (e.g. AV-8B Harrier) have weight, cost and useful load penalties associated with the "vertical" capable engine. Current Air Force aircraft have no real capability to operate from bomb damaged runways. Civil aircraft often resort to exotic high lift systems to operate from short runways, which adds both weight and cost to such aircraft. Certain new concepts such as those applied to the Joint Strike Fighter (JSF) attempt to provide all these capabilities but at significant added weight and cost.
Initial purchase and ownership costs for both military and civil aircraft have become a deciding factor in successive new and upgraded/modified aircraft. Weight is a paramount consideration in determining cost, as well as operational capability/flexibility. A concept is required that will allow very short takeoffs and landings without the traditional weight and cost penalties.
U.S. Pat. No. 2,761,634, issued to J. L. Velazquez, discloses an aircraft that sits statically with a pronounced nose-up attitude. It also uses propellers (and depends on slipstream effects of these propellers) and a very large flap on the wing to prevent stalling.
U.S. Pat. No. 2,971,725, issued to V. J. Jakimiuk, discloses the use of multiple jet engines, two of which rotate to provide thrust vectoring.
U.S. Pat. No. 3,995,794, issued to E. M. Lanier, discloses an aircraft provided with two wings and a top wing having engines attached thereto. The wing and engines are capable of rotating to provide a thrust vectoring effect.
U.S. Pat. No. 5,098,034, issued to W. C. Lendriet, discloses an aircraft having rotating wings with a very complicated flap system and propellers (taking advantage of propeller slipstream effects) in front of the wing blowing over it to prevent stall.
U.S. Pat. No. 4,687,158, issued to C. W. Kettering, discloses a jump strut landing gear apparatus for providing an aircraft with a short takeoff and landing capability. The apparatus utilizes incrementally fired, pyrotechnic charges to explosively generate the required compressed fluid to drive the apparatus.
U.S. Pat. No. 5,351,888 issued to J. D. Taylor, discloses a multi-axis vectorable exhaust nozzle. A convergent-divergent exhaust nozzle is mounted to an exhaust duct of a jet aircraft engine by a circumferentially-spaced set of hydraulic cylinders. The cylinders are interconnected in captured flow via hydraulic circuits, which allow the cylinders to function as a gimbal mounting.
U.S. Pat. No. 4,261,533, issued to Lawrence T. Roberts et al., disclose a technique for control of an aircraft in ultra-deep stall. Tilting the stabilizer at an extreme angle to the fuselage, with leading edge down, and controlling an varying engine thrust comprise a method for all-axis control of a generally conventional aircraft in ultra-deep stall.
U.S. Pat. No. 4,896,846, and its Pat. No. Re. 35,387, both issued to T. H. Strom, disclose a technique to perform a post-stall maneuver for aircraft combat. The aircraft utilizes a highly deflective canard and engine thrust vectoring.
None of the aforementioned patents provide a means of using conventionally mounted jet engines with thrust vectoring, fixed wings, and simple flap systems to affect short takeoffs and landings.